Fibroblast growth factor 19 as a countermeasure to muscle and locomotion dysfunctions in experimental cerebral palsy

BACKGROUND

Cerebral palsy (CP) associates cerebral function damages with strong locomotor defects and premature sarcopenia. We previously showed that fibroblast growth factor 19 (FGF19) exerts hypertrophic effects on skeletal muscle and improves muscle mass and strength in mouse models with muscle atrophy. Facing the lack of therapeutics to treat locomotor dysfunctions in CP, we investigated whether FGF19 treatment could have beneficial effects in an experimental rat model of CP.

METHODS

Cerebral palsy was induced in male Wistar rat pups by perinatal anoxia immediately after birth and by sensorimotor restriction of hind paws maintained until Day 28. Daily subcutaneous injections with recombinant human FGF19 (0.1 mg/kg bw) were performed from Days 22 to 28. Locomotor activity and muscle strength were assessed before and after FGF19 treatment. At Day 29, motor coordination on rotarod and various musculoskeletal parameters (weight of tibia bone and of soleus and extensor digitorum longus (EDL) muscles; area of skeletal muscle fibres) were evaluated. In addition, expression of specific genes linked to human CP was measured in rat skeletal muscles.

RESULTS

Compared to controls, CP rats had reduced locomotion activity (-37.8% of distance travelled, P < 0.05), motor coordination (-88.9% latency of falls on rotarod, P < 0.05) and muscle strength (-25.1%, P < 0.05). These defects were associated with reduction in soleus (-51.5%, P < 0.05) and EDL (-42.5%, P < 0.05) weight, smaller area of muscle fibres, and with lower tibia weight (-38%, P < 0.05). In muscles from rats submitted to CP, changes in the expression levels of several genes related to muscle development and neuromuscular junctions were similar to those found in wrist muscle of children with CP (increased mRNA levels of Igfbp5, Kcnn3, Gdf8, and MyH4 and decreased expression of Myog, Ucp2 and Lpl). Compared with vehicle-treated CP rats, FGF19 administration improved locomotor activity (+53.2%, P < 0.05) and muscle strength (+25.7%, P < 0.05), and increased tibia weight (+13.8%, P < 0.05) and soleus and EDL muscle weight (+28.6% and +27.3%, respectively, P < 0.05). In addition, it reduced a number of very small fibres in both muscles (P < 0.05). Finally, gene expression analyses revealed that FGF19 might counteract the immature state of skeletal muscles induced by CP.

CONCLUSIONS

These results demonstrate that pharmacological intervention with recombinant FGF19 could restore musculoskeletal and locomotor dysfunction in an experimental CP model, suggesting that FGF19 may represent a potential therapeutic strategy to combat the locomotor disorders associated with CP.

Functional and surgical treatments in patients with spinal muscular atrophy (SMA)

Spinal muscular atrophies (SMA type 1, 2, 3) present with various severities according to the motor semeiology related to lesions of the peripheral nervous system (lesions of the anterior horn cells motoneuron or even brain stem). Early motor deficiency causes skeletal deformities responsible for the alteration or even absence of motor skills acquisition. The management of these patients involves several practitioners: pediatric neurologist, pediatric pneumologist, physical medicine and rehabilitation therapist, pediatric orthopedic surgeon, psychologist, physiotherapist, etc. Therefore, this multidisciplinary management must take place in a reference center. This has allowed for improvement of the natural history of SMA. Despite the severity of clinical presentation, especially in SMA type 1 or 2, the functional aspect is always to be taken into account in the first instance. Furthermore, the natural history of the disease is currently being modified by the emergence of innovative therapies that will change the evolution of the disease and its management. Indeed, current treatment objectives are the comfort of installation and the fight against neuro-orthopedic degradation. Although the rise in the number of innovative therapies has led to increased expectancies, such as motor function improvement, practitioners should be aware that these innovative treatments should be balanced against child development and the disease's natural history. Scoliosis surgery is almost systematic in SMA type 2 because of trunk muscular deficiency, especially intercostal muscle insufficiency, and spino-pelvic complex disorder. However, surgical techniques have evolved to become less invasive and more growth friendly in order to follow child development. The final goal of surgery in SMA patients is to obtain a 3-dimensional deformity correction along with a spino-pelvic realignment in order to allow for a comfortable seated position, which is the position of function in these patients, and to allow for better ventilation. Faced with this global approach and innovative therapies, global assessment is warranted not solely in an isolated manner, as is usually the case during hospital stays with traditional scales, but rather during daily activities. This is the case of daily monitoring, which allows for motor skill and activity assessments throughout the day. The principle is to characterize, according to SMA type and treatment, the activity type (standing, seated, walking), duration, intensity and frequency. The ultimate goal would be to identify the variety and occurrence of motor activities, and finally to clarify if the different treatments, including innovative therapies, lead to functional improvement in these patients. © 2020 French Society of Pediatrics. Published by Elsevier Masson SAS. All rights reserved.

Experimental validation of a new technique for the assessment of posterior tibial translation (ABC angle) after posterior cruciate ligament rupture

Background

The aim of this cadaver study was to evaluate an original technique for measuring posterior tibial translation based on an angle value instead of a distance value, with and without posterior stress application. It was hypothesized that an angle measurement of the posterior tibial translation would confirm the presence of a PCL tear with the knee flexed and completely extended.

Method

Using fresh cadavers, a set of strict lateral views were taken by fluoroscopy with the knee at 0°, 45° and 90° flexion on the intact knee and after transecting the PCL. The primary endpoint was the change in the posterior translation measured using a new technique, the ABC angle. This measurement was compared to the conventional posterior translation distance measurement with and without a posterior stress placed on the knee.

Results

Application of a posterior stress revealed clear changes in posterior translation after PCL transection with the knee at 0° for the angle technique and at 45° and 90° for the two techniques (p < 0.05). Contrary to the reference method, the ABC angle method found a statistically significant difference in posterior translation with the knee in extension.

Conclusion

Our technique provides a reliable radiographic measurement of posterior translation with the knee in extension, which should make it easier to acquire radiographs in patients who have pain with knee flexion. This angular measurement also has the advantage of not needing length calibration contrary to the reference technique.

Level of evidence

IV

Obesity activates immunomodulating properties of mesenchymal stem cells in adipose tissue with differences between localizations

Mesenchymal stem cells from healthy adipose tissue are adipocytes progenitors with immunosuppressive potential that are used for years in cell therapy. Whether adipose stem cells (ASC) may prevent inflammation in early obesity is not known. To address this question, we performed a kinetic study of high-fat (HF) diet induced obesity in mice to follow the immune regulating functions of adipose stem cells (ASC) isolated from the subcutaneous (SAT) and the visceral adipose tissue (VAT). Our results show that, early in obesity and before inflammation was detected, HF diet durably and differently activated ASC from SAT and VAT. Subcutaneous ASC from HF-fed mice strongly inhibited the proliferation of activated T lymphocytes, whereas visceral ASC selectively inhibited TNFα expression by macrophages and simultaneously released higher concentrations of IL6. These depot specific differences may contribute to the low-grade inflammation that develops with obesity in VAT while inflammation in SAT is delayed. The mechanisms involved differ from those already described for naïve cells activation with inflammatory cytokines and probably engaged metabolic activation. These results evidence that adipose stem cells are metabolic sensors acquiring an obesity-primed immunocompetent state in answer to depot-specific intrinsic features with overnutrition, placing these cells ahead of inflammation in the local dialog with immune cells.

Milk polar lipids favorably alter circulating and intestinal ceramide and sphingomyelin species in postmenopausal women

BACKGROUND

High circulating levels of ceramides (Cer) and sphingomyelins (SM) are associated with cardiometabolic diseases. The consumption of whole fat dairy products, naturally containing such polar lipids (PL), is associated with health benefits, but the impact on sphingolipidome remains unknown.

METHODS

In a 4-week randomized controlled trial, 58 postmenopausal women daily consumed milk PL-enriched cream cheese (0, 3, or 5 g of milk PL). Postprandial metabolic explorations were performed before and after supplementation. Analyses included SM and Cer species in serum, chylomicrons, and feces. The ileal contents of 4 ileostomy patients were also explored after acute milk PL intake.

RESULTS

Milk PL decreased serum atherogenic C24:1 Cer, C16:1 SM, and C18:1 SM species (P_group < 0.05). Changes in serum C16+18 SM species were positively correlated with the reduction of cholesterol (r = 0.706), LDL-C (r = 0.666), and ApoB (r = 0.705) (P < 0.001). Milk PL decreased chylomicron content in total SM and C24:1 Cer (P_group < 0.001), parallel to a marked increase in total Cer in feces (P_group < 0.001). Milk PL modulated some specific SM and Cer species in both ileal efflux and feces, suggesting differential absorption and metabolization processes in the gut.

CONCLUSION

Milk PL supplementation decreased atherogenic SM and Cer species associated with the improvement of cardiovascular risk markers. Our findings bring insights on sphingolipid metabolism in the gut, especially Cer, as signaling molecules potentially participating in the beneficial effects of milk PL.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02099032, NCT02146339.

FUNDING

ANR-11-ALID-007-01; PHRCI-2014: VALOBAB, no. 14-007; CNIEL; GLN 2018-11-07; HCL (sponsor).

Ed accesses severity for intossication and substance abuse during the first pandemic wave of 2019 coronavirus pandemic (COVID-19). experience of a lombardy ed

Introduction

The 2019 coronavirus epidemic (CoViD-19) in Italy originated in Lombardy, on February 21, 2020. The Fondazione IRCCS Policlinico San Matteo di Pavia has been involved in the management of the outbreak since its beginning

Objectives

We evaluated all the population who went to the ED for intossication and substance abuse to assess the severity of cases evaluated as exit code and rate of hospitalization.

Methods

We enrolled all patients accessing our ED for intossication and substance abuse form February 22 to May 1, 2020 and during the same period of the previous year.

Results

We enrolled 142 patients. 41 in the CoViD period and 101 in 2019. The vital parameters, and sex were overlapping. patients during the pandemic were younger (38 vs 46) The priority codes for the medical examination were not different. CoViD pandemic patients have higher codes (yellow and red) for the medical examination (66% vs 59%); discharge severity codes (red) more frequently than in the reference period (2.4% vs 0.9%) and more frequently need hospitalization (26.8% vs 16.8%).

Conclusions

The epidemic has led to a reduction of accesses for intossication and substance abuse. Patients had more frequent hospitalization needs and more severe exit codes. the data may be due to the fact that during the pandemic only the most serious patients access the E.D., but also to the fact that a pandemic has contributed to destabilizing this class of fragile patients.

Access to E.D. for mental disorders during the first pandemic wave of 2019 coronavirus epidemic (CoViD-19): Presentation and severity at a lombardy ED

Introduction

The 2019 coronavirus epidemic (CoViD-19) in Italy originated in Lombardy, on February 21, 2020. The Fondazione IRCCS Policlinico San Matteo di Pavia has been involved in the management of the outbreak since its beginning. ED’ psychiatric population is considered fragile, at risk of under triage.

Objectives

We evaluated all the population who went to the ED for mental disorder to assess the severity of cases evaluated as exit code and rate of hospitalization.

Methods

We evaluated all patients accessing our ED for mental disorder from February 22 to May 1, 2020 and during the same period of the previous year.

Results

We enrolled 345 patients. There was a severe reduction in the total number of accesses for mental disorder: 142 in the CoViD period and 203 in 2019. The vital parameters, age (mean about 40 years) and sex were overlapping without statistically significant differences. The priority codes for the medical examination were not different. CoViD pandemic patients have higher discharge severity codes (yellow and red) more frequently than in the reference period (9.9% vs 5.9%) and more frequently need hospitalization (25.3% vs 18.6%).

Conclusions

The epidemic has led to a reduction of accesses for mental disorder. Patients had more frequent hospitalization needs and more severe exit codes. the data may be due to the fact that during the pandemic only the most serious patients access the E.D., but also to the fact that a pandemic has contributed to destabilizing this class of fragile patients.

Crowding analysis for patients with intossication and substance abuse during the first pandemic wave of 2019 coronavirus epidemic (COVID-19) at a lombardy ED

Introduction

The 2019 coronavirus epidemic (CoViD-19) in Italy originated in Lombardy, on February 21, 2020. Crowding has been defined as a worldwide problem as cause of reduced quality of care and patient satisfaction. It is due and identified by three orders of factors: those at the access (input); those related to the patient’s process (throughput); and those at the exit from the ED (output).

Objectives

We evaluated all the population who went to ED for intossication and substance abuse. Due to the high level of care needed by these, an excessive duration of LOS (length of Stay) can be counterproductive.

Methods

We evaluated all patients accessing our ED for intossication and substance abuse from February 22 to May 1, 2020 and during the same period of the previous year.

Results

We enrolled 142 patients. The Crowding input factors are lower in the pandemic period: reduced attenders (41 vs 101) and reduced average waiting times (59 min vs 86 min). The Crowding throughput factors have instead worsened: LOS for both the visit rooms (810 vs 544 min) and the holding area (1205 min vs 947 min). The Crowding output factors also worsened: the percentage of access block is higher during the pandemic (10% vs 5%). The Total Access Block Time is significantly higher in the CoViD period for the holding area (1053 vs 930 min).

Conclusions

The pandemic period presented a worsened crowding for these patients due to the Access Block.

Crowding analysis for patients with mental disorders during the first pandemic wave of 2019 coronavirus epidemic (CoViD-19) at a lombardy ED

Introduction

The 2019 coronavirus epidemic (CoViD-19) in Italy originated in Lombardy, on February 21, 2020. Crowding has been defined as a worldwide problem and causes reduced quality of care. It is due and identified by three orders of factors: those at the access (input); those related to the patient’s process (throughput); and those at the exit from the ED (output).

Objectives

We evaluated all the population who went to ED for mental disorder. Due to the high level of care needed and the simultaneous exposure to risk factors, an excessive duration of ED process can be counterproductive.

Methods

We evaluated all patients accessing our ED for mental disorder from February 22 to May 1, 2020 and during the same period of the previous year.

Results

We enrolled 345 patients. The Crowding input factors are lower in the pandemic period: reduced attenders (142 vs 203) and reduced average waiting times (40 min vs 54 min). The Crowding throughput factors have instead worsened: LOS (length of stay) for both visit rooms (383 vs 271 min) and holding area (1735 min vs 797 min). The Crowding output factors also worsened: the percentage of access block is higher during the pandemic (100% vs 20%). The Total Access Block Time is significantly higher in the CoViD period for both the visit rooms (3.239 vs 649 min) and the holding area (590 vs 185 min).

Conclusions

The pandemic period presented a worsened crowding for these patients due to the Access Block.

Between the first and second wave of the 2019 coronavirus pandemic (COVID-19): Presentation and crowding of attenders for mentale disorder and intossication/substance abuse

Introduction

During the 1st wave of CoViD-19 pandemic there was a drastic reduction in total number of accesses, with more serious cases and a exorbitant increase in crowding, due to access block.

Objectives

evaluate population who went to ED for (1) mental disorders requesting a psychiatric visit and for (2) intossication and substance abuse, between the first and second wave of the coronavirus pandemic

Methods

We enrolled all patients who went at our ED from May 1 to October 20, 2020 and during the same period of 2019. We analized: vital parameters, age, sex, exit severity codes, hospitalization rate, Crowding input factors (number of access, waiting time, priority time to doc), Crowding throughput factors (LOS: Length Of ED Stay), Crowding output factors (percentage of access block; Total Access Block Time).

Results

The results are shown in table 1Table 1Mental-disorderintossication/substance-abuseMay1-October 20,2020May1- October 20,2019May1-October 20,2020May1- October 20, 2019number of ED access543564182254higher (yellow and red) priority time to doc (%)28%29%50%39%worse exit severity codes (%)10%6%16%11%rate of hospitalization (%)26%20%16%9%average waiting times (min)60647679LOS lenght of stay (min)369326629506access block (%)3%2%5%4%Total Access Block Time: examination rooms (min)11.5388.3848.0598.889Total Access Block Time: holding area (min)8.3823.963182254

Conclusions

We would like to thank all employees of the IRCCS Policlinico San Matteo Foundation for their extraordinary efforts during the pandemic.

Differential Effect of Glucose on ER-Mitochondria Ca2+ Exchange Participates in Insulin Secretion and Glucotoxicity-Mediated Dysfunction of β-Cells

Glucotoxicity-induced β-cell dysfunction in type 2 diabetes is associated with alterations of mitochondria and the endoplasmic reticulum (ER). Both organelles interact at contact sites, defined as mitochondria-associated membranes (MAMs), which were recently implicated in the regulation of glucose homeostasis. The role of MAMs in β-cells is still largely unknown, and their implication in glucotoxicity-associated β-cell dysfunction remains to be defined. Here, we report that acute glucose treatment stimulated ER-mitochondria interactions and calcium (Ca²⁺) exchange in INS-1E cells, whereas disruption of MAMs altered glucose-stimulated insulin secretion (GSIS). Conversely, chronic incubations with high glucose of either INS-1E cells or human pancreatic islets altered GSIS and concomitantly reduced ER Ca²⁺ store, increased basal mitochondrial Ca²⁺, and reduced ATP-stimulated ER-mitochondria Ca²⁺ exchanges, despite an increase of organelle interactions. Furthermore, glucotoxicity-induced perturbations of Ca²⁺ signaling are associated with ER stress, altered mitochondrial respiration, and mitochondria fragmentation, and these organelle stresses may participate in increased organelle tethering as a protective mechanism. Last, sustained induction of ER-mitochondria interactions using a linker reduced organelle Ca²⁺ exchange, induced mitochondrial fission, and altered GSIS. Therefore, dynamic organelle coupling participates in GSIS in β-cells, and over time, disruption of organelle Ca²⁺ exchange might be a novel mechanism contributing to glucotoxicity-induced β-cell dysfunction.

Omega-3 Polyunsaturated Fatty Acids Inhibit IL-17A Secretion through Decreased ICAM-1 Expression in T Cells Co-Cultured with Adipose-Derived Stem Cells Harvested from Adipose Tissues of Obese Subjects

SCOPE

Obese adipose tissue (AT) is infiltrated by inflammatory immune cells including IL-17A-producing-T (Th17) cells. It has been previously demonstrated that adipose-derived stem cells from obese (ob-ASCs), but not lean AT promote Th17 cells. Because n-3 PUFAs are known to inhibit obese AT inflammation, it is tested here whether they could inhibit ob-ASC-mediated IL-17A secretion.

METHODS AND RESULTS

The n-3 PUFA precursor, alpha-linolenic acid (ALA), or its derivatives, eicosapentaenoic, or docosahexaenoic acid, is added to co-cultures of human ob-ASCs and mononuclear cells (MNCs). All three inhibited IL-17A, but not IL-1β, IL-6, nor TNFα  secretion. As a control, palmitic acid (PA), a saturated fatty acid, did not inhibit IL-17A secretion. ALA also inhibited IL-17A secretion mediated by adipocytes differentiated from ob-ASCs. Toll-like-receptor 4 is shown to be involved in ob-ASC-mediated-IL-17A secretion, and to be inhibited by ALA, together with Cyclo-Oxygenase-2 and Signal-Transducer-and-Activator-of-transcription-3. In addition, ALA down-regulated Intercellular-Adhesion-Molecule-1 (ICAM-1) expression in both monocytes and ASCs, which resulted in decreased interactions between ob-ASCs and MNCs, and inhibition of IL-17A secretion.

CONCLUSION

It is demonstrated herein that ALA inhibits Th17 cell promotion, through decreased ICAM-1expression in both ob-ASCs and monocytes. This novel mechanism may contribute to explain the beneficial effects of n-3 PUFA in IL-17A-related inflammatory pathologies.

Human mesenchymal stem cells improve rat islet functionality under cytokine stress with combined upregulation of heme oxygenase-1 and ferritin

Background

Islets of Langerhans transplantation is a promising therapy for type 1 diabetes mellitus, but this technique is compromised by transplantation stresses including inflammation. In other tissues, co-transplantation with mesenchymal stem cells has been shown to reduce damage by improving anti-inflammatory and anti-oxidant defences. Therefore, we probed the protection afforded by bone marrow mesenchymal stem cells to islets under pro-inflammatory cytokine stress.

Methods

In order to evaluate the cytoprotective potential of mesenchymal stem cells on rat islets, co-cultures were exposed to the interleukin-1, tumour necrosis factor α and interferon γ cocktail for 24 h. Islet viability and functionality tests were performed. Reactive oxygen species and malondialdehyde were measured. Expression of stress-inducible genes acting as anti-oxidants and detoxifiers, such as superoxide dismutases 1 and 2, NAD(P)H quinone oxidoreductase 1, heme oxygenase-1 and ferritin H, was compared to non-stressed cells, and the corresponding proteins were measured. Data were analysed by a two-way ANOVA followed by a Holm-Sidak post hoc analysis.

Results

Exposure of rat islets to cytokines induces a reduction in islet viability and functionality concomitant with an oxidative status shift with an increase of cytosolic ROS production. Mesenchymal stem cells did not significantly increase rat islet viability under exposure to cytokines but protected islets from the loss of insulin secretion. A drastic reduction of the antioxidant factors heme oxygenase-1 and ferritin H protein levels was observed in islets exposed to the cytokine cocktail with a prevention of this effect by the presence of mesenchymal stem cells.

Conclusions

Our data evidenced that MSCs are able to preserve islet insulin secretion through a modulation of the oxidative imbalance mediated by heme and iron via heme oxygenase-1 and ferritin in a context of cytokine exposure.

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1190-4) contains supplementary material, which is available to authorized users.

Circumferential minimally invasive approach for low-grade isthmic spondylolisthesis: A clinical and radiological study of 43 patients

INTRODUCTION

Circumferential fusion for lumbar low-grade isthmic spondylolisthesis (LGIS) provides the best spinal stability and highest fusion rates. The aim of this study is to investigate results of minimal invasive management of LGIS and correlations between Intervertebral Foramen Surface (IFS) and other parameters.

METHODS

We retrospectively reviewed cases of 43 patients who underwent a minimally invasive circumferential fusion (Anterior lumbar interbody fusion followed by percutaneous posterior pedicle screw fixation) for LGIS between January 2010 and December 2014 in our institution. Inclusion criteria were one-level (L4-L5 or L5-S1) LGIS with low back and/or radicular pain. Pre- and postoperative radiographic evaluations were performed at 6, 12 and 24months. Measurements (Percentage of anterior displacement, degree of slip angle, height of the intervertebral space and the IFS) were obtained using Surgimap^®.

RESULTS

Nineteen patients (44.2%) were males. Mean age was 43 years old (19-72years). The mean follow-up of the series was 18.3months (3-72months). Mean preoperative Visual Analogy Scale (VAS) for low back pain decreased from 70mm to 20mm and from 80mm to 10mm as to radicular pain. Anterior displacement was reduced from 18% to 7% (p<0.01), degree of slippage were increased from 9.8° to 15.2° (p<0.01), intervertebral height was restored from 4.4mm to 8.5mm (p<0.01) and increase of the IFS was calculated 48.8%.

CONCLUSION

One stage circumferential fixation for adults' LGIS without decompression, allows restoration of intervertebral height permitting good reduction of the slippage, an increasing of the IFS and liberation of nerve roots.

Trends in the surgical management of odontoid fractures in patients above 75 years of age: Retrospective study of 70 cases

BACKGROUND

Odontoid fractures are the most common upper cervical spine fracture in adults over 70 years of age. Hence, treatment of these fractures has public health implications.

OBJECTIVES

Evaluate the early complications, bone healing and mortality in patients above 75 years of age who undergo surgical treatment of an odontoid fracture. Compare the results between patients operated with the Harms technique or anterior screw fixation.

METHODS

This was a retrospective study of 70 patients with an odontoid fracture who were treated surgically between 2000 and 2015 at the Hôpital de la Timone in France. The age at the time of diagnosis, comorbidities, ASA score and autonomy were evaluated. Bone healing was determined using computed tomography.

RESULTS

In the cohort, 22 patients underwent anterior screw fixation, 38 were treated using the Harms technique and 10 with other procedures. The average age was 85.1 years. Fifty-four percent of patients had an ASA score above 3. The average follow-up was 23.4 months. An Anderson type II fracture was present in 80.6% of patients. In the anterior screw fixation group, the operative time was significantly shorter than in the Harms group and no blood transfusions were needed. However, 13.6% of these patients had to be re-operated because the initial construct was unstable; no patients in the Harms group underwent revision surgery. There were more complications in the anterior screw fixation group than in the Harms group: 41% versus 13.2% (P<0.02). The fractures had healed in all patients reviewed after 1 year. The 3-month survival in the anterior screw fixation group was 64.7% and it was 81.3% in the Harms group. These rates were stable at 1 year with no statistical differences between groups.

CONCLUSION

Surgical treatment of odontoid fractures in the elderly results in an excellent union rate. The mortality rate is stable after 3 months. In our experience, the Harms technique has a lower risk of complications and better mechanical stability than anterior screw fixation. Despite the steep learning curve, we believe the Harms technique is probably the best choice for treating odontoid fractures in the elderly.

LEVEL OF EVIDENCE

IV.

Low level activity thresholds for changes in NMR biomarkers and genes in high risk subjects for Type 2 Diabetes

Our objectives were to determine if there are quantitative associations between amounts and intensities of physical activities (PA) on NMR biomarkers and changes in skeletal muscle gene expressions in subjects with high risk for type 2 diabetes (T2D) performing a 3-month PA intervention. We found that PA was associated with beneficial biomarker changes in a factor containing several VLDL and HDL subclasses and lipids in principal component analysis (P = <0.01). Division of PA into quartiles demonstrated significant changes in NMR biomarkers in the 2nd - 4th quartiles compared to the 1st quartile representing PA of less than 2850 daily steps (P = 0.0036). Mediation analysis of PA-related reductions in lipoproteins showed that the effects of PA was 4-15 times greater than those of body weight or fat mass reductions. In a subset study in highly active subjects' gene expressions of oxidative fiber markers, Apo D, and G0/G1 Switch Gene 2, controlling insulin signaling and glucose metabolism were significantly increased. Slow walking at speeds of 2-3 km/h exceeding 2895 steps/day attenuated several circulating lipoprotein lipids. The effects were mediated rather by PA than body weight or fat loss. Thus, lower thresholds for PA may exist for long term prevention of cardio-metabolic diseases in sedentary overweight subjects.

Operative management of supracondylar humeral fractures in children: Comparison of five fixation methods

BACKGROUND

The best method for stabilising supracondylar humeral fractures (SHFs) in children remains unclear. The objective of this study was to compare the outcomes of five different fixation methods for SHFs in children.

HYPOTHESIS

Differences in intra-operative and short-term post-operative parameters can be demonstrated across different fixation methods for SHFs in children.

PATIENTS AND METHODS

We reviewed the medical files of paediatric patients managed at our centre between 2006 and 2016 for SHF with major displacement (type 3 or 4 in the Lagrange-Rigault classification). Clinical and radiological parameters collected post-operatively and at last follow-up included Baumann's angle, anteversion of the distal humeral epiphysis, and operative time. Over the 11-year study period, 251 patients were included; mean age was 6.4 years and mean follow-up 4.7 months. The five fixation methods used were elastic stable intra-medullary nailing (ESIN, n=16), two pins in an X configuration (n=33), two lateral pins and one medial pin (n=144), two lateral pins (n=33), and three lateral pins (n=25). A minimally invasive 2-cm approach was used to insert the medial pins. Immediate instability of the fixation was considered in patients with an at least 15° deficit in Baumann's angle or anteversion, or with rotational malalignment, on the radiographs taken on day 1. Outcomes were analysed in each of the five internal fixation groups.

RESULTS

Immediate instability showed no significant differences across the five groups. Operative time was significantly shorter with two lateral pins (33min, P=0.046). Time to hardware removal was longer in the ESIN group (54 days, P=0.03). Use of a medial pin was associated with a lower risk of secondary displacement (2.0% vs. 8.6%, P=0.04) but did not affect the risk of nerve injury (4% vs. 3%, P=0.86).

DISCUSSION

This is one of the largest retrospective cohort studies of outcomes according to the fixation technique used to treat SHFs in children. Adding a medial pin through a minimally invasive approach is associated with a longer operative time but limits the risk of secondary displacement without increasing the frequency of iatrogenic nerve injury and improves fracture site stability. Use of a medial pin therefore deserves to be considered in paediatric SHFs.

LEVEL OF EVIDENCE

IV, retrospective cohort study.

Evaluation of the external fixator TrueLok Hexapod System for tibial deformity correction in children

BACKGROUND

Tibial deformities are common in paediatric orthopaedic practice. Correcting multiplanar tibial deformities associated with lower limb length discrepancy can be challenging. Hexapod external fixation with gradual correction has been proven effective in this situation.

OBJECTIVE

To assess clinical and radiological outcomes of gradual tibial deformity correction using the external fixator TL-HEX™ (Orthofix) in children.

HYPOTHESIS

TL-HEX™ is effective in correcting tibial deformities in children.

PATIENTS AND METHODS

This multicentre retrospective study collected data from the medical files of 26 patients with 31 tibial deformities treated by gradual correction using TL-HEX™. The tibial deformities were due to congenital defects in 11 (35%) cases, Blount's disease in 9 (29%) cases, pseudo-achondroplasia in 4 (13%) cases, and other causes in 7 (23%) cases. Mean age at surgery was 11.9 years. In each patient, antero-posterior long leg radiographs obtained pre-operatively and at last follow-up were used to measure parameters including the mechanical axis deviation (MAD), medial proximal tibia angle (MPTA), and leg length discrepancy (LLD).

RESULTS

The mean healing index was 39.3 days/cm (range, 32-58 days/cm). The overall complication rate was 61%, with 11 unplanned visits. Superficial pin tract infection was the most common complication. Significant decreases between the pre-operative and post-operative assessments occurred in mean MAD (from 32.1mm to 10.2mm, P<0.001) and mean LLD (from 36.8mm to 9.1mm, P<0.001). Patients who underwent proximal tibial osteotomy had a significant improvement in MPTA, from 80.6° to 88.5° (P=0.006).

DISCUSSION

This is the first clinical study specifically designed to assess outcomes of TL-HEX™ limb lengthening and deformity correction. MAD, MPTA, and LLD were significantly improved at last follow-up. MAD was greater than 10mm at last follow-up in only 11patients. The complication rate was similar to those reported with other external fixators. TL-HEX™ is effective in the management of tibial deformities in children.

LEVEL OF EVIDENCE

IV (retrospective study).

Low-dose pollutant mixture triggers metabolic disturbances in female mice leading to common and specific features as compared to a high-fat diet

Environmental pollutants are potential etiologic factors of obesity and diabetes that reach epidemic proportions worldwide. However, it is important to determine if pollutants could exert metabolic defects without directly inducing obesity. The metabolic disturbances triggered in nonobese mice lifelong exposed to a mixture of low-dose pollutants (2,3,7,8-tetrachlorodibenzo-p-dioxine, polychlorinated biphenyl 153, diethylhexyl-phthalate, and bisphenol A) were compared with changes provoked by a high-fat high-sucrose (HFHS) diet not containing the pollutant mixture. Interestingly, females exposed to pollutants exhibited modifications in lipid homeostasis including a significant increase of hepatic triglycerides but also distinct features from those observed in diet-induced obese mice. For example, they did not gain weight nor was glucose tolerance impacted. To get more insight, a transcriptomic analysis was performed in liver for comparison. We observed that in addition to the xenobiotic/drug metabolism pathway, analysis of the hepatic signature illustrated that the steroid/cholesterol, fatty acid/lipid and circadian clock metabolic pathways were targeted in response to pollutants as observed in the diet-induced obese mice. However, the specific sets of dysregulated annotated genes (>1300) did not overlap more than 40% between both challenges with some genes specifically altered only in response to pollutant exposure. Collectively, results show that pollutants and HFHS affect common metabolic pathways, but by different, albeit overlapping, mechanisms. This is highly relevant for understanding the synergistic effects between pollutants and the obesogenic diet reported in the literature.

Surgical management of post-traumatic atlantoaxial rotatory fixation due to C2 facet fracture: 5 clinical cases

PURPOSE

Report the results of surgical treatment of post-traumatic atlantoaxial rotatory fixation (AARF) due to C2 articular facet fracture in adults.

MATERIAL AND METHODS

The records of five patients treated since 2009 for AARF due to a C2 articular facet fracture were analyzed retrospectively. Three women and two men with an average age of 60 years (27-82) were included, one of whom initially had neurological deficits. In all cases, the surgical strategy consisted of posterior fixation: Harms-type in four cases and trans-articular with hooks in one case.

RESULTS

Dislocations due to fracture of the C2 articular facet are rare in adults; various treatment strategies have been described. In our experience, posterior screw fixation leads to satisfactory clinical and radiological outcomes. Fusion is not necessary in these cases because the dislocation is related to an asymmetric fracture without ligament damage.

CONCLUSION

Posterior fixation provides satisfactory reduction of these injuries and leads to satisfactory bone union. This surgical treatment can be performed early on after the trauma and is an interesting alternative to conservative treatment.

Intraoperative spinal cord monitoring: Lesional level diagnosis

BACKGROUND

In spinal deformity surgery, iatrogenic spinal cord injury is the most feared complication. Intraoperative monitoring (IOM) of the spinal cord assesses its functional integrity and allows significant reduction of the rate of spinal cord injury.

HYPOTHESIS

In case of severe IOM alert, lesional level diagnosis constitutes supplementary and useful information.

MATERIAL AND METHODS

This study was retrospective and monocentric. In our institution, 1062 pediatric spinal deformity surgeries have been monitored since 2004. We review the records of the six patients who presented a severe and prolonged IOM alert with lesional level determination. Somatosensory evoked potentials (SSEP), neurogenic mixed evoked potentials (NMEP) and D-waves were performed. In cases of IOM alert, sequentially moving an epidural electrode along the spinal cord allows lesional level determination, using this electrode either for stimulation or recording.

RESULTS

Six patients, aged 12 to 17 years, characterized by severe IOM alerts during spinal deformity surgery are reported. Postoperative neurological examination was normal for five out of six cases. For patient 2, lesional level diagnosis allowed to determine a bi-laminar claw between T2 and T3 as the etiology of IOM alert. This IOM alert was delayed in time, being detectable only 30minutes after the placement of this claw. Postoperative neurological examination was normal. For patient 6, a Stagnara wake-up test demonstrated paraplegia. Lesional level was established. Following corrective surgical maneuvers, postoperative neurologic deficit was limited to a pyramidal syndrome in one lower limb. Postoperative MRI demonstrated a spinal cord lesion at the determined lesional level.

CONCLUSION

During an IOM alert, lesional level determination allows localization of spinal cord dysfunction. This data, obtainable whatever the IOM device, constitutes supplementary information in order to rapidly identify the etiology of IOM alert and thus to react in the most appropriate way.

LEVEL OF EVIDENCE

IV, retrospective study.

Impact of surgical correction of a U-shaped sacral fracture on sagittal spino-pelvic alignment: Regarding one case

U-shaped sacral fractures are uncommon and are mostly the consequence of a high-energy kinetic trauma. The sacrum is a crucial element for sagittal alignment in a standing position as it determines the value of the pelvic incidence, which is a fixed and unchanging parameter for a given individual. We report the case of a 21-year-old man who underwent corrective surgery for a type II U-shaped fracture of the sacrum (according to the Roy-Camille classification), associated with a S1-S2 dislocation and sacral kyphosis that modified the patient's pelvic incidence. At one-year follow-up, radiographic examinations revealed solid bony fusion and stable results after removal of the implants. The surgery was managed for neurological decompression, stabilization of the fracture and correction of sacral kyphosis. The restoration of the theoretical pelvic incidence depended on the estimated lumbar lordosis. The aim of this study was to highlight the particularities in the management of a sacral U-shaped fracture and their relationship with the sagittal alignment.

Transplantar intramedullary locking nailing in childhood congenital pseudarthrosis of the tibia: A report of 3 cases

The treatment objectives in congenital pseudarthrosis of the tibia are bone consolidation and a restored lower-limb axis. They are difficult to achieve, and various surgical techniques have been described, with varying results in terms of bone consolidation and complications. The present study reports clinical and radiographic results in 3 patients managed by the same original technique of transplantar intramedullary nailing using a custom-made proximal locking nail, without surgical approach or resection of the pseudarthrosis site. Good assembly stability allowed immediate weight-bearing. The technique is relatively noninvasive, offering a first-line alternative in under-3 year-olds.

Exosome-like vesicles released from lipid-induced insulin-resistant muscles modulate gene expression and proliferation of beta recipient cells in mice

AIMS/HYPOTHESIS

The crosstalk between skeletal muscle (SkM) and beta cells plays a role in diabetes aetiology. In this study, we have investigated whether SkM-released exosome-like vesicles (ELVs) can be taken up by pancreatic beta cells and can deliver functional cargoes.

METHODS

Mice were fed for 16 weeks with standard chow diet (SCD) or with standard diet enriched with 20% palmitate (HPD) and ELVs were purified from quadriceps muscle. Fluorescent ELVs from HPD or SCD quadriceps were injected i.v. or intramuscularly (i.m.) into mice to determine their biodistributions. Micro (mi)RNA quantification in ELVs was determined using quantitative real-time RT-PCR (qRT-PCR)-based TaqMan low-density arrays. Microarray analyses were performed to determine whether standard diet ELVs (SD-ELVs) and high palmitate diet ELVs (HPD-ELVs) induced specific transcriptional signatures in MIN6B1 cells.

RESULTS

In vivo, muscle ELVs were taken up by pancreas, 24 h post-injection. In vitro, both SD-ELVs and HPD-ELVs transferred proteins and miRNAs to MIN6B1 cells and modulated gene expressions whereas only HPD-ELVs induced proliferation of MIN6B1 cells and isolated islets. Bioinformatic analyses suggested that transferred HPD-ELV miRNAs may participate in these effects. To validate this, we demonstrated that miR-16, which is overexpressed in HPD-ELVs, was transferred to MIN6B1 cells and regulated Ptch1, involved in pancreas development. In vivo, islets from HPD mice showed increased size and altered expression of genes involved in development, including Ptch1, suggesting that the effect of palm oil on islet size in vivo was reproduced in vitro by treating beta cells with HPD-ELVs.

CONCLUSIONS/INTERPRETATION

Our data suggest that muscle ELVs might have an endocrine effect and could participate in adaptations in beta cell mass during insulin resistance.

Feasibility of a reduction protocol in the emergency department for diaphyseal forearm fractures in children

INTRODUCTION

Diaphyseal forearm fractures are very common pediatric traumas. At present, distal radius metaphyseal fractures are often successfully treated with closed reduction by emergency physicians. However, the management of diaphyseal fractures remains controversial. The purpose of this study was to analyze the results of diaphyseal forearm fractures in the emergency department (ED) in children.

MATERIALS AND METHODS

In a prospective 2-year-study, all closed diaphyseal forearm fractures in patients under 15, with an angle of >15° and treated by closed reduction in the ED were included. Fractures with overlapping fragments were excluded. Reduction was performed by an emergency physician, with a standardized analgesic protocol (painkillers and nitrous oxide). Clinical tolerance was checked within the first 24hours, and the radiographic stability of reduction was assessed at days 8 and 15. Initial and final follow-up radiographs were analyzed. Elbow and wrist range of motion was assessed at the final follow-up.

RESULTS

Sixty patients (41 boys and 19 girls) were included. Mean age was 5.2 years old (±3). At initial evaluation, the maximum angle was 30° (±11.3). After reduction, the maximum angle was significantly reduced (30° vs. 5°, P<0.001). Mean immobilization in a cast was 11.7 weeks (±2). There were no cast related complications in any of these children. There was no surgery for secondary displacement. Full range of motion was obtained in all patients at the final follow-up.

DISCUSSION

The outcome of conservative treatment of closed diaphyseal forearm fractures, without overlapping fragments was excellent. However, reduction is usually performed in the operating room by orthopedic surgeons under general anesthesia and requires hospitalization, which is very expensive. The results of this study show that high quality care may be obtained in the ED by a trained and experienced team. These results are similar to those for distal metaphyseal fractures, which could extend the indications for reduction in the ED.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Evolution of adolescent idiopathic scoliosis: results of a multicenter study at 20 years' follow-up

INTRODUCTION

To date there is no consensus on therapeutic indications in adolescent idiopathic scoliosis (AIS) with curvature between 30° and 60° at the end of growth.

OBJECTIVE

The objective of this study was to assess outcome in patients with moderate AIS.

MATERIAL AND METHODS

A multicenter retrospective study was conducted. Inclusion criteria were: Cobb angle, 30-60° at end of growth; and follow-up > 20 years. The data collected were angular values in adolescence and at last follow-up, and quality of life scores at follow-up.

RESULTS

A total of 258 patients were enrolled: 100 operated on in adolescence, 116 never operated on, and 42 operated on in adulthood. Mean follow-up was 27.8 years. Cobb angle progression significantly differed between the 3 groups: 3.2° versus 8.8° versus 23.6°, respectively; P < 0.001. In lumbar scoliosis, the risk of progression to ≥ 20° was significantly higher for initial Cobb angle > 35° (OR=4.278, P=0.002). There were no significant differences in quality of life scores.

DISCUSSION

Patients operated on in adolescence showed little radiological progression, demonstrating the efficacy of surgical treatment for curvature greater than 50°. Curvature greater than 40° was progressive and may require surgery in adulthood. Lumbar scoliosis showed greater potential progression than thoracic scoliosis in adulthood, requiring fusion as of 35° angulation.

LEVEL OF EVIDENCE

IV, retrospective study.

Postprandial Endotoxemia Linked With Chylomicrons and Lipopolysaccharides Handling in Obese Versus Lean Men: A Lipid Dose-Effect Trial

CONTEXT

Postprandial endotoxemia is a metabolic risk factor, which has been shown to originate from the intestinal absorption of gut lipopolysaccharides (LPS) using nonphysiological high-fat tests.

OBJECTIVE

This study aimed to determine whether different realistic fat amounts can modulate postprandial dynamics and handling of LPS by varying postprandial lipidemia in humans of different body mass indices.

DESIGN, SETTING, AND PARTICIPANTS

In a randomized, controlled, cross-over study in nutrition research center, eight normal-weight (NW) and eight obese age-matched men, without diabetes nor dyslipidemia, ingested breakfasts containing 10 vs 40 g fat. Blood samples, leukocytes, and chylomicron-rich fractions were obtained during 8 h. Plasma and chylomicron-endotoxemia, plasma LPS transporters (LBP, sCD14) and IL-6, nuclear factor κB (NF-κB) translocation, and IL-6 gene expression of immune cells were measured.

MAIN OUTCOME

The postprandial fatty acid handling after ingesting 40 g fat was previously published as primary outcome. The secondary outcomes were inflammatory ones including postprandial endotoxemia, LPS handling, and plasma markers of inflammation after ingesting 10 or 40 g fat.

RESULTS

Chylomicronemia increased in all subjects according to ingested fat amount (P < .01), but only obese had higher postprandial endotoxemia after 40 g (P < .05). Obese subject chylomicrons were more enriched with LPS compared with NW (PBMI < .01). We observed neither NF-κB translocation, nor variation of IL-6 expression in leukocytes. In both groups, fat amount did not modify postprandial response of plasma IL-6. However, the area under the curve (AUC) of IL-6 in obese was higher than in NW (P < .05) parallel to higher fasting LPS-binding protein (LBP; P < .05). AUC of IL-6 was correlated with LBP (P < .01).

CONCLUSION

Postprandial endotoxemia is modulated by ingested fat amount in obese men. LPS handling in plasma through chylomicrons and LBP seems critical in driving the acute inflammatory response. The pathophysiological importance of repeated postprandial endotoxemia excursions and their contribution to a vicious cycle of LBP-driven low-grade inflammation deserve further investigation in the nutritional management of cardio-metabolic risk prevention.

Ozone exposure triggers insulin resistance through muscle c-Jun N-terminal kinase activation

A growing body of evidence suggests that exposure to traffic-related air pollution is a risk factor for type 2 diabetes. Ozone, a major photochemical pollutant in urban areas, is negatively associated with fasting glucose and insulin levels, but most aspects of this association remain to be elucidated. Using an environmentally realistic concentration (0.8 parts per million), we demonstrated that exposure of rats to ozone induced whole-body insulin resistance and oxidative stress, with associated endoplasmic reticulum (ER) stress, c-Jun N-terminal kinase (JNK) activation, and disruption of insulin signaling in skeletal muscle. Bronchoalveolar lavage fluids from ozone-treated rats reproduced this effect in C2C12 myotubes, suggesting that toxic lung mediators were responsible for the phenotype. Pretreatment with the chemical chaperone 4-phenylbutyric acid, the JNK inhibitor SP600125, or the antioxidant N-acetylcysteine alleviated insulin resistance, demonstrating that ozone sequentially triggered oxidative stress, ER stress, and JNK activation to impair insulin signaling in muscle. This study is the first to report that ozone plays a causative role in the development of insulin resistance, suggesting that it could boost the development of diabetes. We therefore provide a potential mechanism linking pollutant exposure and the increased incidence of metabolic diseases.

Exosomes participate in the alteration of muscle homeostasis during lipid-induced insulin resistance in mice

AIMS/HYPOTHESIS

Exosomes released from cells can transfer both functional proteins and RNAs between cells. In this study we tested the hypothesis that muscle cells might transmit specific signals during lipid-induced insulin resistance through the exosomal route.

METHODS

Exosomes were collected from quadriceps muscles of C57Bl/6 mice fed for 16 weeks with either a standard chow diet (SD) or an SD enriched with 20% palm oil (HP) and from C2C12 cells exposed to 0.5 mmol/l palmitate (EXO-Post Palm), oleate (EXO-Post Oleate) or BSA (EXO-Post BSA).

RESULTS

HP-fed mice were obese and insulin resistant and had altered insulin-induced Akt phosphorylation in skeletal muscle (SkM). They also had reduced expression of Myod1 and Myog and increased levels of Ccnd1 mRNA, indicating that palm oil had a deep impact on SkM homeostasis in addition to insulin resistance. HP-fed mouse SkM secreted more exosomes than SD-fed mouse SkM. This was reproduced in-vitro using C2C12 cells pre-treated with palmitate, the most abundant saturated fatty acid of palm oil. Exosomes from HP-fed mice, EXO-Post Palm and EXO-Post Oleate induced myoblast proliferation and modified the expressions of genes involved in the cell cycle and muscle differentiation but did not alter insulin-induced Akt phosphorylation. Lipidomic analyses showed that exosomes from palmitate-treated cells were enriched in palmitate, indicating that exosomes likely transfer the deleterious effect of palm oil between muscle cells by transferring lipids. Muscle exosomes were incorporated into various tissues in vivo, including the pancreas and liver, suggesting that SkM could transfer specific signals through the exosomal route to key metabolic tissues.

CONCLUSIONS/INTERPRETATION

Exosomes act as 'paracrine-like' signals and modify muscle homeostasis during high-fat diets.

Myotube-derived exosomal miRNAs downregulate Sirtuin1 in myoblasts during muscle cell differentiation

It has recently been established that exosomes can mediate intercellular cross-talk under normal and pathological conditions through the transfer of specific miRNAs. As muscle cells secrete exosomes, we addressed the question of whether skeletal muscle (SkM) exosomes contained specific miRNAs, and whether they could act as "endocrine signals" during myogenesis. We compared the miRNA repertoires found in exosomes released from C2C12 myoblasts and myotubes and found that 171 and 182 miRNAs were exported into exosomes from myoblasts and myotubes, respectively. Interestingly, some miRNAs were expressed at higher levels in exosomes than in their donor cells and vice versa, indicating a selectivity in the incorporation of miRNAs into exosomes. Moreover miRNAs from C2C12 exosomes were regulated during myogenesis. The predicted target genes of regulated exosomal miRNAs are mainly involved in the control of important signaling pathways for muscle cell differentiation (e.g., Wnt signaling pathway). We demonstrated that exosomes from myotubes can transfer small RNAs (C. elegans miRNAs and siRNA) into myoblasts. Moreover, we present evidence that exosome miRNAs secreted by myotubes are functionally able to silence Sirt1 in myoblasts. As Sirt1 regulates muscle gene expression and differentiation, our results show that myotube-exosome miRNAs could contribute to the commitment of myoblasts in the process of differentiation. Until now, myokines in muscle cell secretome provided a conceptual basis for communication between muscles. Here, we show that miRNA exosomal transfer would be a powerful means by which gene expression is orchestrated to regulate SkM metabolic homeostasis.

Traumatic inter-condylar dislocation of the patella: report of two cases

Traumatic patellar dislocation usually occurs in the lateral direction. In a few cases, however, the patella rotates around its horizontal axis and becomes wedged between the femoral condyles. We report two cases of traumatic inter-condylar patellar dislocation that required surgical management.

High-fat diet action on adiposity, inflammation, and insulin sensitivity depends on the control low-fat diet

Animal studies using a high-fat diet (HFD) have studied the effects of lipid overconsumption by comparing a defined HFD either with a natural-ingredient chow diet or with a defined low-fat diet (LFD), despite the dramatic differences between these control diets. We hypothesized that these differences in the control diet could modify the conclusions regarding the effects that an increase of fat in the diet has on several metabolic parameters. For 11 weeks, C57bl6/J mice were fed a low-fat chow diet (8% energy from fat), a typical semisynthetic LFD (12%), or a semisynthetic HFD (sy-HF) (40%). Conclusions about the effect of sy-HF on body weight gain, subcutaneous adipose tissue, insulin sensitivity, and adipose tissue inflammation were modified according to the control LFD. Conversely, conclusions about epididymal and retroperitoneal adipose tissue; fat intake effects on liver and muscular lipids, cholesterol, free fatty acids, and markers of low-grade inflammation; and of adipose tissue macrophage infiltration were the same regardless of the use of low-fat chow diet or semisynthetic LFD. For some physiological outcomes, conflicting conclusions were even reached about the effects of increased fat intake according to the chosen low-fat control. Some deleterious effects of sy-HF may not be explained by lipid overconsumption but rather by the overall quality of ingredients in a semisynthetic diet. According to the control LFD chosen, conclusions on the lipid-related effects of HFDs must be formulated with great care because some end points are profoundly affected by the ingredient composition of the diet rather than by fat content.

Grape polyphenols prevent fructose-induced oxidative stress and insulin resistance in first-degree relatives of type 2 diabetic patients

OBJECTIVE

To assess the clinical efficacy of nutritional amounts of grape polyphenols (PPs) in counteracting the metabolic alterations of high-fructose diet, including oxidative stress and insulin resistance (IR), in healthy volunteers with high metabolic risk.

RESEARCH DESIGN AND METHODS

Thirty-eight healthy overweight/obese first-degree relatives of type 2 diabetic patients (18 men and 20 women) were randomized in a double-blind controlled trial between a grape PP (2 g/day) and a placebo (PCB) group. Subjects were investigated at baseline and after 8 and 9 weeks of supplementation, the last 6 days of which they all received 3 g/kg fat-free mass/day of fructose. The primary end point was the protective effect of grape PPs on fructose-induced IR.

RESULTS

In the PCB group, fructose induced 1) a 20% decrease in hepatic insulin sensitivity index (P < 0.05) and an 11% decrease in glucose infusion rate (P < 0.05) as evaluated during a two-step hyperinsulinemic-euglycemic clamp, 2) an increase in systemic (urinary F2-isoprostanes) and muscle (thiobarbituric acid-reactive substances and protein carbonylation) oxidative stress (P < 0.05), and 3) a downregulation of mitochondrial genes and decreased mitochondrial respiration (P < 0.05). All the deleterious effects of fructose were fully blunted by grape PP supplementation. Antioxidative defenses, inflammatory markers, and main adipokines were affected neither by fructose nor by grape PPs.

CONCLUSIONS

A natural mixture of grape PPs at nutritional doses efficiently prevents fructose-induced oxidative stress and IR. The current interest in grape PP ingredients and products by the global food and nutrition industries could well make them a stepping-stone of preventive nutrition.

FTO is increased in muscle during type 2 diabetes, and its overexpression in myotubes alters insulin signaling, enhances lipogenesis and ROS production, and induces mitochondrial dysfunction

OBJECTIVE

A strong association between genetic variants and obesity was found for the fat mass and obesity-associated gene (FTO). However, few details are known concerning the expression and function of FTO in skeletal muscle of patients with metabolic diseases.

RESEARCH DESIGN AND METHODS

We investigated basal FTO expression in skeletal muscle from obese nondiabetic subjects and type 1 and type 2 diabetic patients, compared with age-matched control subjects, and its regulation in vivo by insulin, glucose, or rosiglitazone. The function of FTO was further studied in myotubes by overexpression experiments.

RESULTS

We found a significant increase of FTO mRNA and protein levels in muscle from type 2 diabetic patients, whereas its expression was unchanged in obese or type 1 diabetic patients. Moreover, insulin or glucose infusion during specific clamps did not regulate FTO expression in skeletal muscle from control or type 2 diabetic patients. Interestingly, rosiglitazone treatment improved insulin sensitivity and reduced FTO expression in muscle from type 2 diabetic patients. In myotubes, adenoviral FTO overexpression increased basal protein kinase B phosphorylation, enhanced lipogenesis and oxidative stress, and reduced mitochondrial oxidative function, a cluster of metabolic defects associated with type 2 diabetes.

CONCLUSIONS

This study demonstrates increased FTO expression in skeletal muscle from type 2 diabetic patients, which can be normalized by thiazolidinedione treatment. Furthermore, in vitro data support a potential implication of FTO in oxidative metabolism, lipogenesis and oxidative stress in muscle, suggesting that it could be involved in the muscle defects that characterize type 2 diabetes.

Persistent organic pollutant exposure leads to insulin resistance syndrome

BACKGROUND

The incidence of the insulin resistance syndrome has increased at an alarming rate worldwide, creating a serious challenge to public health care in the 21st century. Recently, epidemiological studies have associated the prevalence of type 2 diabetes with elevated body burdens of persistent organic pollutants (POPs). However, experimental evidence demonstrating a causal link between POPs and the development of insulin resistance is lacking.

OBJECTIVE

We investigated whether exposure to POPs contributes to insulin resistance and metabolic disorders.

METHODS

Sprague-Dawley rats were exposed for 28 days to lipophilic POPs through the consumption of a high-fat diet containing either refined or crude fish oil obtained from farmed Atlantic salmon. In addition, differentiated adipocytes were exposed to several POP mixtures that mimicked the relative abundance of organic pollutants present in crude salmon oil. We measured body weight, whole-body insulin sensitivity, POP accumulation, lipid and glucose homeostasis, and gene expression and we performed microarray analysis.

RESULTS

Adult male rats exposed to crude, but not refined, salmon oil developed insulin resistance, abdominal obesity, and hepatosteatosis. The contribution of POPs to insulin resistance was confirmed in cultured adipocytes where POPs, especially organochlorine pesticides, led to robust inhibition of insulin action. Moreover, POPs induced down-regulation of insulin-induced gene-1 (Insig-1) and Lpin1, two master regulators of lipid homeostasis.

CONCLUSION

Our findings provide evidence that exposure to POPs commonly present in food chains leads to insulin resistance and associated metabolic disorders.

Claudin 11 deficiency in mice results in loss of the Sertoli cell epithelial phenotype in the testis

Tissue integrity relies on barriers formed between epithelial cells. In the testis, the barrier is formed at the initiation of puberty by a tight junction complex between adjacent Sertoli cells, thereby defining an adluminal compartment where meiosis and spermiogenesis occur. Claudin 11 is an obligatory protein for tight junction formation and barrier integrity in the testis. It is expressed by Sertoli cells, and spermatogenesis does not proceed beyond meiosis in its absence, resulting in male sterility. Sertoli cell maturation--arrest of proliferation and expression of proteins to support germ cell development--parallels tight junction assembly; however, the pathophysiology underlying the loss of tight junctions in the mature testis remains largely undefined. Here, using immunohistochemistry and microarrays we demonstrate that adult Cldn11(-/-) mouse Sertoli cells can proliferate while maintaining expression of mature markers. Sertoli cells detach from the basement membrane, acquire a fibroblast cell shape, are eliminated through the lumen together with apoptotic germ cells, and are found in epididymis. These changes are associated with tight junction regulation as well as actin-related and cell cycle gene expression. Thus, Cldn11(-/-) Sertoli cells exhibit a unique phenotype whereby loss of tight junction integrity results in loss of the epithelial phenotype.

Microarray analysis of genes with impaired insulin regulation in the skeletal muscle of type 2 diabetic patients indicates the involvement of basic helix-loop-helix domain-containing, class B, 2 protein (BHLHB2)

AIMS/HYPOTHESIS

One of the major processes by which insulin exerts its multiple biological actions is through gene expression regulation. Thus, the identification of transcription factors affected by insulin in target tissues represents an important challenge. The aim of the present study was to gain a greater insight into this issue through the identification of transcription factor genes with insulin-regulated expression in human skeletal muscle.

METHODS

Using microarray analysis, we defined the sets of genes modulated during a 3 h hyperinsulinaemic-euglycaemic clamp (2 mU min(-1) kg(-1)) in the skeletal muscle of insulin-sensitive control volunteers and in moderately obese insulin-resistant type 2 diabetic patients.

RESULTS

Of the 1,529 and 1,499 genes regulated during the clamp in control and diabetic volunteers, respectively, we identified 30 transcription factors with impaired insulin-regulation in type 2 diabetic patients. Analysis of the promoters of the genes encoding these factors revealed a possible contribution of the transcriptional repressor basic helix-loop-helix domain-containing, class B, 2 protein (BHLHB2), insulin regulation of which is strongly altered in the muscle of diabetic patients. Gene ontology analysis of BHLHB2 target genes, identified after BHLHB2 overexpression in human primary myotubes, demonstrated that about 10% of the genes regulated in vivo during hyperinsulinaemia are potentially under the control of this repressor. The data also suggested that BHLHB2 is situated at the crossroads of a complex transcriptional network that is able to modulate major metabolic and biological pathways in skeletal muscle, including the regulation of a cluster of genes involved in muscle development and contraction.

CONCLUSIONS/INTERPRETATION

We have identified BHLHB2 as a potential novel mediator of insulin transcriptional action in human skeletal muscle.

The effects of an in utero exposure to 2,3,7,8-tetrachloro-dibenzo-p-dioxin on male reproductive function: identification of Ccl5 as a potential marker

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and dioxin-like compounds are widely encountered toxic substances suspected of interfering with the endocrine systems of humans and wildlife, and of contributing to the loss of fertility. In this study, we determined the changes in testicular gene expression caused by in utero exposure to TCDD along with the intra-testicular testosterone levels, epididymal sperm reserves, daily sperm production (DSP) and testis histology. To this purpose, female pregnant Sprague-Dawley rats orally received TCDD (10, 100 or 200 ng/kg body weight) or vehicle at embryonic day 15, and the offspring was killed throughout development. Hepatic Cyp1a1 gene expression was measured in the offspring to confirm the exposure to TCDD. The gross histology of the testes and intra-testicular testosterone levels were normal among the studied groups. Sperm reserves were altered in 67-day-old rats of the TCDD-200 group, but not in 145-day-old animals or in the other TCDD-exposed groups. Nonetheless, fertility was not altered in males of the TCDD-200 group, and the F2 males generated had normal sperm reserves and DSP. Microarray analysis permitted the identification of eight differentially expressed genes in the 4-week-old testes of the TCDD-200 compared with that of the control group (cut-off value +/- 1.40), including the down-regulated chemokine Ccl5/Rantes. Inhibition of Ccl5/Rantes gene expression was observed throughout development in the TCDD-200 group, and at 67 and 145 days in the TCDD-100 group (animals of younger ages were not examined). Ccl5/Rantes gene expression was mostly confined in Leydig cells. F2 males generated from males of the TCDD-200 group had normal levels of Ccl5/Rantes in testis and Cyp1a1 in liver, which might indicate that Ccl5/Rantes is a marker of TCDD exposure in testis such as Cyp1a1 in liver. In conclusion, we demonstrated a decrease in Ccl5/Rantes RNA levels and a transitory decline in sperm reserves in the testes of rats of TCDD-dosed dams.

Using the DREEM-Italian Version to Evaluate the Recovery-Orientation of Pavia Rehabilitative Services

We assessed the recovery-orientation of the Pavia Rehabilitation Services using an Italian Version of the DREEM (Developing Recovery Enhancing Environment Measure). A preliminary Italian Version of the DREEM was translated by the first author (MB) and a back-translation was carried out by a trained translator (MT). A third member of the research team (JS) resolved disagreements between the two versions by discussion and consensus with MB and MT. The final version was administered to the patients of the rehabilitation services of Pavia. 15 patients out of a possible 21 (71.4%) participated in the first interview. Demographic information including gender (53% male, 47% female), age range (26-35 years: 27%, 36-45 years: 33%, 46-55 years: 27%, 56-65 years: 6%, 66 years and over: 7%), ethnicity (Italian: 100%) was collected. 20% had been using mental health services for between 5 and 10 years, and 80% for more than 10 years. The section “elements of recovery and recovery enhancing services” scored 1.2 for “importance ratings for recovery elements” and 2.4 for “staff performance”, with a performance gap of 1.2. Mean scores for “organizational climate” and “recovery markers” were 2.3 in both sections. The mean score of 1.2 on the importance ratings shows that patients have a good understanding of recovery elements. The other scores reveal a fairly good recovery orientation of the service, but with a wide margin for improvements as indicated by the performance gap. The Italian version of the DREEM is useful; the results can promote reflections, discussion and learning within the staff.